How modify main.cf smtpd_data_restrictions

Hi people, i want modify smtpd_data_restrictions, smtpd_end_of_data_restrictions and smtpd_client_restrictions, if i modify direct in main.cf when restart the services main.cf back to the original file, mean no changes allowed??

Fisrt i change smtpd_recipient_restrictions with /opt/zimbra/conf/postfix_recipient_restrictions.cf

But now need change smtpd_data_restrictions, smtpd_end_of_data_restrictions and smtpd_client_restrictions but i cant modify.